Field of the Disclosure
The present disclosure, for example, relates to wireless communication systems, and more particularly to estimation of phase noise.
Description of Related Art
Wireless communication systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be multiple-access systems capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include code-division multiple access (CDMA) systems, time-division multiple access (TDMA) systems, frequency-division multiple access (FDMA) systems, and orthogonal frequency-division multiple access (OFDMA) systems.
By way of example, a wireless multiple-access communication system may include a number of base stations, each simultaneously supporting communication for multiple communication devices, otherwise known as user equipments (UEs). A base station may communicate with UEs on downlink channels (e.g., for transmissions from a base station to a UE) and uplink channels (e.g., for transmissions from a UE to a base station).
Wireless communication systems may suffer from phase noise, which can be more pronounced in systems operating in higher frequencies, e.g., operating in the millimeter wave (mmW) frequency ranges, e.g., 28 GHz, 40 GHz, 60 GHz, etc. This may be due to a higher frequency ratio between a local oscillator and other oscillators. On the UE side, the UEs are typically made with lower quality parts (e.g., oscillators), which also contribute to phase noise generation. This phase noise can create non-negligible variations in phase over the duration of a single symbol, e.g., symbols may be shorter in higher frequency systems.